Curcumin ameliorates TNF-α-induced ICAM-1 expression and subsequent THP-1 adhesiveness via the induction of heme oxygenase-1 in the HaCaT cells

Abstract

Adhesion molecules such as ICAM-1 are important in theinfiltration of leukocytes into the site of inflammation. In thisstudy, we investigated the inhibitory effects of curcumin onICAM-1 expression and monocyte adhesiveness as well as itsunderlying action mechanism in the TNF-α-stimulated keratinocytes.Curcumin induced expression of heme oxygenase-1(HO-1) in the human keratinocyte cell line HaCaT. In addition,curcumin induced Nrf2 activation in dose- and time-dependentmanners in the HaCaT cells. Curcumin suppressed TNF-α-induced ICAM-1 expression and subsequent monocyte adhesion,which were reversed by the addition of tin protoporphyrinIX (SnPP), a specific inhibitor of HO-1, or HO-1knockdown using siRNA. Furthermore, Nrf2 knockdown usingsiRNA reversed the inhibitory effect of curcumin on theTNF-α-induced ICAM-1 expression and adhesion of monocytesto keratinocytes. These results suggest that curcumin may exertits anti-inflammatory activity by suppressing the TNF-α-inducedICAM-1 expression and subsequent monocyte adhesion viaexpression of HO-1 in the keratinocytes. [BMB Reports 2013;46(8): 410-415]

Keywords

• Curcumin
• HO-1
• ICAM-1
• Inflammation
• Keratinocyte